This award supports Professor Abraham M. Lenhoff of the University of Delaware for collaborative research with Professor Klaus K. Unger of the Institute for Inorganic and Analytical Chemistry of Johannes Gutenberg University, Mainz, Federal Republic of Germany. The objective of their research is to gain a better understanding of the role of adsorption and desorption kinetics in hydrophobic interaction chroma- tography (HIC) of proteins. The information sought is significant for both analytical and preparative systems. It sets a fundamental limit for the speed of microanalytical separations, and it provides rate information that can be important in optimizing the design and operation of preparative columns for this form of chromatography. Two complementary analytic approaches will be used, both involving the same proteins, surface characteristics and solvent compositions. The first involves the use of Total Internal Reflectance Fluorescence (TIRF) spectroscopy for the direct, real-time measurement of adsorption and desorption kinetics and equilibria on a flat slide. The second uses HIC with a 1.5 micron non-porous stationary phase to examine behavior in actual column chromatography under conditions where kinetics are likely to be rate-limiting. Comparison of the results of the two sets of experiments will be made possible by the transport and kinetic modelling of the respective systems. The planned cooperation combines the TIRF capability and the modelling strengths of the Delaware group with the surface synthesis expertise of the Mainz group.
